Longitudinal floor frame members connect to a vehicle floor and form components of a vehicle frame structure. Vehicles typically include two main longitudinal floor frame members, one on each side of a longitudinal centerline of the vehicle. For minivans, vans and other similar vehicles, the main longitudinal floor frame members can transition in height through the same area in a longitudinal direction as a sliding door opening of the vehicle.
During a frontal crash event, the mass of the rear portion of the vehicle continues forward. During a crash event, frame members tend to give at transition areas, e.g., bends and changes in height, of the frame member. Since the main longitudinal floor frame members transition in height through the same area as the sliding door opening, higher deformation of the vehicle body can occur in the sliding door opening during a frontal crash event.